Electric size-controlling gauge



July 19, 1955 s. A. FOSTER 2,713,207

ELECTRIC SIZE-CONTROLLING GAUGE Filed Aug. 15, 1952 2 Sheets-Sheet l I N VEN TOR.

July 19, 1955 s. A. FOSTER 2,713,207

ELECTRIC SIZE-CONTROLLING GAUGE Filed Aug. 13, 1952 2 Sheets-Sheet 2 fey 3.

IN VEN TOR.

QS'MJ a. $00M Unite rates Patent fiice 2,713,207 Fatented July 19, 1955 ELEC'IEIC SIZE-CONTROLLING GAUGE Shuhel A. Foster, Birmingham, Mich, assignor to The Foster Engineering Corporation, Royal Oak, Mich., a corporation of Michigan Application August 13, 1952, Serial No. 304,080

3 Claims. (Cl. 33--147) In my U. S. Patent No. 2,267,559, granted to me December 3, 1941, I describe a gauge mechanism electrically coupled to a motor for controlling the grinding of Work in a machine whereby, when the precise diameter or dimension desired of the work is obtained, the resultant automatic operation of the gauge will cause a current to flow through a relay which, in turn, will break the motor circuit and thereby shut ofi further grinding operation on the work.

In many cases it is desirable that an intermediate step be interposed in the grinding operation whereby, when grinding has proceded to a point approaching completion, the grinding operation would be modified by slowing down rotation of the grinding wheel during the completion stage, or by slowing the feed-in rate, or by both a slower wheel speed and a slower feed-in rate where this arrangement may be desirable.

To this end, I have devised a duplex gauge mechanism which can quite conveniently admit of the use of two manually adjustable gap elements and gauge block mechanisms such as are described in my said Patent No. 2,267,559 (details of which will be further referred to hereinafter), one of these gauge mechanisms being adapted to operate only on the completion of the grinding operation and the other mechanism to operate when the grinding operation is approaching completion to an extent determined by the manual setting of that mechanism.

The present invention involves the provision for the relative setting of the two gauge mechanisms in order to regulate the differential of their operation in such a manner that this differential between them will be maintained regardless of the setting of that mechanism which controls the stopping of the machine upon the completion of the work to meet the particular work size to be ground in the machine; and the invention still further contemplates the protective concealment of the difierentialregulating means in such a manner it is not so freely accessible to an operator or to others as to render it liable to be inadvertently or undesirably disturbed as to the diflerential setting. 1

A further object or the said invention is-to provide means for varying the difierential setting which will be simple to operate, capable of variation even to a very slight but definitely determined extent, and capable of determination as to the extent of such variation in averyaccurate manner and by simple procedure without reference to calibrations or similar measuring means.

I More particularly, the said invention contemplates the provision of a pair of micrometer screws, the relative setting of which determines the operational difierential between the two gauge mechanisms, the said screws being geared together so that the operation of one of the micrometer screws will result in the synchronized operation of the other; and means, in the form of an idler geared therebetween, adapted tobe temporarily disengaged to permit the rotary adjustment of one of the said micrometer screws independently of the other for variably setting the operational difierential between the two gauge mechanisms.

Still further objects or advantages additional or subsidiary to the aforesaid objects, or resulting from the construction or operation of the invention as it may be carried into effect, will become apparent as the said invention is hereinafter further disclosed.

In carrying the said invention into effect, i may adopt the novel construction and arrangement of parts hereinafter described, by way of example, having reference to the accompanying drawings, wherein:

Figure l is a schematic drawing of my improved dif ferential gauge as applied to two electric circuits such as may control, firstly, the modified or slowed down operation and, secondly, the stopping of the operation of a grinding machine;

Figure 2 is a vertical section, taken on a plane indicated by the line 22 in Figure 3, of the body or casing of the gauge showing one of the switch controlling mechanisms;

Figure 3 is a horizontal section of the same taken on a plane indicated by the line 33 in Figure 2;

Figure 4 is a partial front elevation of the gauge;

Figure 5 is a fragmentary vertical section taken on a plane indicated by the line 55 in Figure 2;

Figure 6 is a partial vertical section taken on a plane indicated by the line 66 in Figure 2;

Figure 7 is a longitudinal vertical section through the idler coupling gear taken on a plane indicated by the line 7-1 in Figure 5;

Figure 8 is a horizontal section showing the micrometer screws and their geared coupling taken on a plane indicated by the line 88 in Figure 2; and

Figure 9 is a detail side elevation of the gauge resetting lever.

Similar characters of reference indicate similar parts in the several figures of the drawings.

As best seen in Figure 3, the present device includes two gauge mechanisms generally indicated by the reference letters A and B shown as being more specifically of the construction, more specifically described in my co-application Serial No. 289,155 filed May 21, 1952, now Patent No. 2,666,993, issued January 26, 1954 being an improved type of that described in my earlier Patent No. 2,267,559 hereinbefore referred to.

Both of these mechanisms, in this case, are mounted in a common carrier 11 which is vertically adjustable in a casing by means of the micrometer 12 (shown in Figure 2). Each of the said mechanisms A and B includes a pair of levers 13 and 14 (hereinafter termed gap elements) which are pivoted at 15 and 16 respectively, each gap element 13 being shown as provided with a pair of rounded wear-resisting projections 17, while each element 14 is similarly provided with a wear-resisting projection 18 whereby an adjustable gap is formed between the projections 17 and the projections 18.

' :14 is a rearwardly extending arm connected to the pivot of the levers 14 and swingable with the said levers, this arm being underthe influence of a light spring which maintains it in impingement with one of the faces 19 of a notch in a plunger 19 carried by the upper end of a gauge rod 20, which rod is biased in a downward i the agency of said arm 14 operate one of the said gauge mechanisms (for example, the mechanism A), upon the work becoming ground to the final diameter. In that case, the purpose of the mechanism B would be to operate at a stage of grinding somewhat prior to the corn- 3 pletion thereof for the purpose which will be further explained.

As in the device described in my earlier Patent No. 2,267,559, the width of the spacing between the .projections of either of the two gauge mechanisms A and B at any moment is determined by three factors; the vertical positioning Within the casing of the carrier 7 11 on which the gap members 13 and 14 are both .piv-

otally mounted; the vertical position of the plunger 19 is determined by the diameter of the work engaged by the lower end of the gauge rod 20; and the angular position of the adjustment of the gap member 13 on its pivot 15 is determined by the setting of the micrometer spindle 27 in the case of'the mechanism A and the spindle 27 in the case of the mechanism'B, each of which micrometer spindles impinges against the elongated depending leg of its respective gap member 13 and urges it against the resistance of the spring 31.

Each pair of gap members of the mechanisms A and B has arranged between them a vertically extending reciprocal stem 24 downwardly biased by the spring 25, and each of the said stems carries a switch contact 26 movable downwardly therewith to close upon a second switch contact 26' mounted on the carrier 11. Each of said stems 24 has also secured thereon a gauge block 2-8 having arcuate or similarly formed surfaces presented in the direction of the wear-resisting projections '17 and 18 of its respective gap elements 13 and 14, whereby downward motion of one or other of said gauge blocks 28 28 between and beyond the wear-resisting projections of the gap elements will close its associated contact 26 and. 26' and thereby close a circuit through the leads A or B, according to which of the gauge mechanisms A or B is operated, to permit its gauge block 28 to pass downwardly between its respective gap elements.

In the schematic diagram of Figure l, the said leads 'A are shown as being electrically connected with a relay 40 controlling the operation of a solenoid .1, such as may be utilized in a grinding machine to operate controls (not shown) such as are well-known in the art for etfecting a slowed-down grinding operation; and the leads B are shown as being similarly connected with the relay 42 intended, when excited, to open an electric circuit through the motor 43 thereby shutting off the operation caused to release their gauge blocks 28 at differing and predetermined stages in the grinding of the work.

Thus, while the gap members of the mechanism B may beset (bythe adjustment of the micrometer spindle 27) to release their associated gap member 28 at the moment the diameter of the work 23 is reduced to its finish limit and the resultant closing of the circuit B thus caused to terminate the grinding action of themachine with which the gauge is used, the gap members of the mechanism A may be 'similarly'set (by adjustment of the micrometer spindle 27') to release their associciated gap member 28 somewhat prior to the finish limit 'members of the mechanism B whereby they may be of the work whereby the closing of the electrical circuit 1 A will result in the operation of the solenoid 41 to slow down the grinding operation of the associated ma-' chine during the further completion of the grinding operation.

Provision is made not only for the operation of the micrometer spindles 27 and 27" in unison, whereby the operational difierential between the two gauge mechanisms A and B may be preserved regardless of the setish diameter of the work, but provision is also made whereby this dilierential may be varied to suit conditions wherein the slowing down of the grinding operation may be desired at difiering periods in'advance of the. work attaining its finish diameter.

The foregoing provisions are effected by means of gear wheels 32 and 32' secured on the inner ends of the micrometer spindles 27 and 27, respectively, and coupled together by an intermediate gear 33 which is rotatable on a member 34 carried by the frame 10 and is secured thereon by the screw 35 which may be removed to permit the disengagement of the said gear 33 from the gears 32 and 32.

It will be apparent that with these three gears in mesh, thee adjustment or" the micrometer spindle 27 (by manual rotation of its operating nut 34) will vary the critical gap opening of the gauge mechanism B accompanied by synchronous adjustment of the micrometer spindle 27, thereby maintaining the operational differential between the gauge mechanisms A and B; but, by simply removing the intermediate gear 33, the micrometer spindle 27 may be adjusted independently of the spindle 27 toeithei' increase or decrease the operational differential between the two gauge. mechanisms A and B. The intermediate gear 33 may be then replaced to again synchronize the rotation of the micrometer spindles 27 .and 27 so that the gauge mechanism B may thereafter be adjusted to the work, either by adjustment of the frame micrometer 12 why the micrometer 27, while the newly determined difierential between the mechanisms A and B is again maintained.

If it be considered that the threads of the micrometer spindles are, say, forty to the inch, and that each of the 7 gears 32 and 32' have fifteen teeth, it will be readily seen that, by simply rotating one of these gears independently through one tooth of its engagement with the intermediate gear 33, a quite fine change in the operation difierential between the two gauge mechanisms will have been obtained and that the range of such relative adjustment may be considerable but accurate to a very close degree.

The gears 32, 32, casing of the device, are efiectively concealed from tampering or unwarranted alteration of their meshing which may only be efiected upon removal of the front plate of the body 16; but the general adjustment of the microm'et'ers 12 and 27 is available to the operator, as is desirable, without requiring the opening up of the body of the device.

37 illustrates a lifter bar extending beneath the lower ends of both of the gauge block stems 24,- the said bar 37 being mounted on the upper end of a stem 38 which may be raised, against the action of a spring 39, by a manually operable lifting lever 46 whereby the resetting of the gauge blocks 28, to their upper position above their respective gap elements prior to putting the gauge.

in operation on the work, may be efiected.

This invention may be developed within the scope of a 7 when said plunger movesan additional predetermined distance, the second of said mechanisms operates; a mic'rometer meansconnected with each of said mechanisms for adjusting the point of operation of said mechanisms, means coupling said micrometer means whereby move ting of the gauge mechanism B to meet the desired, finmen: of one of said micrometer means causes relative and 33, being arranged within the D movement of the other of said micrometer means to maintain synchronous operation of said gauge mechanisms.

2. In a gauge of the type described, a Work-piece e11- gaging movable plunger, a pair of adjustable Work-gauging mechanisms each responsive to movement of said plunger whereby when said plunger moves a predetermined distance the first of said mechanisms operates and when said plunger moves an additional distance the second of said mechanisms operates; a micrometer means connected with each of said gauge mechanisms for adjusting the point of operation or" each of said mechanisms, means coupling said micrometer means whereby movement of one of said micrometer means causes relative movement of the other of said micrometer means to maintain synchronous operation of said gauge mechanisms, said coupling means being removable to permit manual adjustment of the relative synchronism of said gauge mechanisms.

3. In a gauge of the type described, a Work-piece engaging movable plunger, a pair of adjustable work-gaugin mechanisms each responsive to movement of said plunger whereby when said plunger moves a predetermined distance, the first of said mechanisms operates and when said plunger moves an additional distance, the second of said mechanisms operates; a micrometer means connected with each of said gauge mechanisms for adjusting the point of operation of each of said mechanisms; a rotatable gear connected to each of said micrometer means and a detachable coupling gear normally meshed with said micrometer connected gears whereby movement of one of said micrometer means causes relative movement of said second micrometer means, said coupling gear being removable so that one of said micrometer means may be adjusted to permit change of the relative synchronism of said mechanisms, after which said coupling gear may be replaced to retain said changed synchronism.

References Cited in the file of this patent UNITED STATES PATENTS 352,520 Courlander Nov. 16, 1886 1,420,700 Hofiman June 27, 1922 2,254,313 Poock et al Sept. 2, 1941 2,384,519 Aller Sept. 11, 1945 

